Impact of Channel Estimation Errors in Cooperative Transmission over Nakagami-m Fading Channels

Abstract

SUMMARYIn this paper, we analyze the impact of channel estimation errors for both decode-and-forward (DF) and amplify-and-forward (AF) cooperative communication systems over Nakagami-m fading channels. Firstly, we derive the exact one-integral and the approximate expressions of the symbol error rate (SER) for DF and AF relay systems with different modulations. We also present expressions showing the limitations of SER under channel estimation errors. Secondly, in order to quantify the impact of channel estimation errors, the average signal-to-noise-ratio (SNR) gap ratio is investigated for the two types of cooperative communication systems. Numerical results confirm that our theoretical analysis for SER is very efficient and accurate. Comparison of the average SNR gap ratio shows that DF model is less susceptible to channel estimation errors than AF model. key words: cooperative communication systems, channel estimation errors, average symbol error rate (SER), average signal-noise-ratio (SNR) gap ratio

Feedback-aided pilot placement for two-way cooperative-OFDM

“…In [8], it was examined that channel estimation error results in lower average signal-tonoise ratio (SNR) and higher average error rate. Motivated by the bad impact of channel estimation error on the relay transmission scenario, we propose an iterative pilot allocation (IPA) scheme.…”